William hochhausen



(No Model.)

W. HOOHHAUSEN.

SHORT GIROUITING SWITCH FOR DYNAMO ELECTRIC MACHINES.

No. 252,663. Patented Jan. 24,1882.

.dttorn UNITED STATES PATENT OFFICE.

l/VILLIAM HOCHHAUSEN, OF NEW YOJRK, N. Y.

SHORT-CIRCUITING SWITCH FOR UYNAMO ELECTRtC MACHINES.

SPECIFICATION forming part of Letters Patent No. 252,663, dated January 24, 1882.

Application filed November 7, 1881.

To all whom it may concern:

Be it known that 1, WILLIAM HOCHHAUSEN, of the city, county, and State of New York, have invented certain new and useful Improvements in Switch Apparatus for Dynamo- *Electric Machines, of which the followingis a specification.

The object of my invention is to prevent the excessive spark which occurs when the current flowing from a dynamo-electricmachineissuddenly interrupted.

It is a well-known fact that when the main or principal circuit of a dynamo-electric machine supplying one or several lights is suddenly broken an excessive spark occurs, this being due, as is generally understood, to what is known as the extra current. This extra current, being of a high tension, oftenbreaks through the insulation of the helices upon the machine and does serious damage, while the spark which occurs at the switch-points at the moment of disruption burns the switch.

The object of my invention is to prevent the extra current, so far as-may be, and to protect the helices ofthe machine and the switch-points from injury. This I accomplish by forming a short circuit around the field-of-force magnets of the machine when the switch is turned for the purpose of cutting oft the flow ofcurrent to the main circuit,the short circuit being formed before the main circuit isinterrupted. By this means the field-of-force magnets are robbed of the current which energizes them, so as to materially decrease the strength -of the current generated, while at the same time the current which would otherwise flow to line is also diverted into the short circuit. Theshort circuit, as above set forth, having been first formed, when the switch is turned farther to break the connection with the main line, but little if any extra current is apparent. My invention may be therefore said to consist in combining with a dynamo-electric machine 5 continuity-preserving switch adapted to break the connection of the machine with the main line, one of the points of said switch being connected to the main circuit, while its other point is connected to a branchadapted to form a short circuit around the field-of-force magnets of themachine. v

Having now described the general principles (No model.)

of my invention, Iwill proceed to describe one kind of apparatus that may be used for carrying the same into effect.

In the accompanyingdrawing I have shown a diagram representing an old form of dynamoelectric machine connected to a main line containing several lights in circuit, and to a cutoff switch with circuit-connections made according to my invention.

A and B represent the fieldof-force magnets of any dynamo-electric machine; a, 1), their curved pole-pieces; andgh, collectoror commutator brushes applied to the surface of a commutator-cylinder, to which the coils of the armaturerotatingbetween the field-of-force poles are connected in any well-known manner. One of the commutator-brushes is connected, as is ordinarily the case, with one of the main-line bintling-posts, 1, whilethe other brush is connected with the helices upon the field-of-force magnets, and through said helices with the other binding-post,2. The main-line wires are represented by the figures 7 and 8, and are shown as including at]? several electric lamps in circuit. Switch-lever S is connected with binding-post 1, and the switch-pointK fol-said lever with one of the main-line wires. The other switch-point L for thelever is connected to a loop or branch wire, 10, runningt'rom the collector-brush g. The point of the switch-lever is split, as shown, or formed in other suitable manner, so as to preserve the contact in passing from one point to the other and to make full and prolonged contact with one point before breaking contact with the other. Thele-ver may heturned, as is well understood, to connect wholly with point K or with point L. hen in contact with K the circuit is from collector-brush h of the armature, through the switch-lever S, point K, main-circuit wire 7, lights at P, wire 8, field of-t'orcc coils, collectorbrush g, and through the coils of the armature to brush h, thus completing the circuit. Under these conditions the machine ist'eedingthe circuit in the well-known manner, and the current generated in the armature-helices being cariied through the field-ot-force helicesincrcases the strength of the field of-force magnetism, which latter reacts upon the armature. It the switch were turned so as to breakthe main circuit, no switchpoint L being provided, there would be a flash and spark between S and L, which would burn the contacts, while, moreover, the extra current to which the tlash is due being of high tension would be liable to break through and destroy the insulation of the wires upon the fieldof-force magnets. As, however, the switch is turned to first make contact with Land loop 10 before breakingthe main-line connection, ashort circuit is provided for the current from the armature-helices, the circuit being through h, 1, S, L, 10, and g, and as the field of-t'orce magnets are thus robbed of theirenergizing-current the strength ot'the current generated is simultaneously and immediately largely diminishcdl At the same time the current is also short-circuited from the line. \Vhen, now, the movement of the switch is completed so as to break the mainline connection at K, scarcely any spark will occur.

IL LIA M HOG ll TTAUSEN.

Witnesses:

H. G. TOWNSEND, FRED. G. DiETERIOII. 

